The bonds, to be sold by the end of the month, come due in November 2019.
By comparison, a year ago SolarCity sold $230m worth of convertible senior notes due in 2018 bearing an interest rate of 2.75%.
In addition to selling bonds, SolarCity continues to raise money large sums of tax-equity finance from banks and other institutional investors, and this summer sold its third round of securitised solar notes.
The